Error setting foreground process group

[Kevin P. Kleinfelter]

I have written my own version of login for my RS/6000.
It runs through the login prompt, gets a password, execs /bin/ksh,
and the terminal prints a shell prompt.
The user can run anything in the background, and can run anything
from his .profile, BUT running anything in the foreground gets the message

   Ksh: Error setting foreground process group

My assumption is that ksh is trying to set the terminal process group
to the process group of the process it created to exec the foreground
command (via ioctl (x, TIOCSPGRP, y)).
I have verified that the process id of the shell, the terminal
process group, and the process group of the shell are all the
same.

What do I need to do to make this problem go away?

(As an explanation as to why I need to do this, I have a program that
will wait for a "login:" prompt, and it then sends a user-id.  This program
is in the hands of a lot of users.  The program sends the user-id
IMMEDIATELY after the "login:" prompt.  It appears that tsm/getty/login
is doing something to flush the input queue after printing "login:" and
before reading the prompt.  Unfortunately, the program in the users'
hands was tested on a system that did not exhibit this behavior.)
-- 
Kevin Kleinfelter @ Dun and Bradstreet Software, Inc (404) 239-2347
{emory,gatech}!nanovx!msa3b!kevin

Look closely at the return address.  It is nanovx and NOT nanovAx.